ABC’s flagship evening news broadcast just chalked up a first in its history, winning the evening news ratings battle for a full year in the key C3 metric.

The New York Post reports that ABC’s “World News Tonight with David Muir” came out on top of “NBC Nightly News” — albeit by a slim margin — in C3 for the key news demo of adults 25-54.

Nielsen’s C3 ratings, also known as “Commercial Ratings,” are a measure of commercial viewing in the live broadcast along with DVR playback up to three days later.

Some disclaimers may be in order. Nielsen first rolled out the C3 measurement in 2007, and the past year was a turbulent period for NBC’s “Nightly News,” with Brian Williams suspended from the program and Lester Holt filling in for six months — temporarily at first, until he was recently given the anchor’s chair on a permanent basis.

“Muir, who recently racked up an interview with Pope Francis, notched 1.972 million viewers in the category, while NBC came in at 1.967 million for the year through Sept. 20,” the Post reports. The story notes that insiders at ABC, which is about to debut an ad campaign trumpeting the ratings victory, report that ad revenue for “World News Tonight” is up 11% from a year ago.

“The 41-year-old Muir, who took the reins from Diane Sawyer in September 2014, is in an all-out dog-fight with Holt, who draws the most total viewers each evening,” the Post notes.

Holt, 56, appears to have righted the ship since being named permanent anchor. NBC News says Holt has been on top in C3 since June 22.